Compilare: user.cpp: In function ‘int getval(std::string&)’: user.cpp:69:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(; pos < s.length() ; pos++){ ^ user.cpp: In function ‘int main()’: user.cpp:99:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("zeap.in","r",stdin); ^ user.cpp:100:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("zeap.out","w",stdout); ^